From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753381Ab2IWAVN (ORCPT ); Sat, 22 Sep 2012 20:21:13 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:40132 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751636Ab2IWAVM (ORCPT ); Sat, 22 Sep 2012 20:21:12 -0400 Date: Sat, 22 Sep 2012 17:21:05 -0700 From: "Paul E. McKenney" To: Sasha Levin Cc: Michael Wang , Dave Jones , "linux-kernel@vger.kernel.org" , fweisbec@gmail.com Subject: Re: RCU idle CPU detection is broken in linux-next Message-ID: <20120923002105.GA1112@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20120921121346.GD2458@linux.vnet.ibm.com> <505C6B03.7020305@gmail.com> <20120921151203.GA2454@linux.vnet.ibm.com> <505C855F.3060301@gmail.com> <505D7621.4040505@gmail.com> <20120922150913.GA2934@linux.vnet.ibm.com> <505DDBE7.7010706@gmail.com> <20120922155613.GB2934@linux.vnet.ibm.com> <505DFA65.3080805@gmail.com> <20120922212735.GG2934@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120922212735.GG2934@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12092300-2876-0000-0000-00000067825F Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 22, 2012 at 02:27:35PM -0700, Paul E. McKenney wrote: > On Sat, Sep 22, 2012 at 07:50:29PM +0200, Sasha Levin wrote: > > On 09/22/2012 05:56 PM, Paul E. McKenney wrote: > > > And now the prime suspect is the new CONFIG_RCU_USER_QS=y. Do these > > > warnings ever show up with CONFIG_RCU_USER_QS=n? > > > > It seems that disabling that does make the warnings go away. > > > > I'll keep the tests running in case it just reduces the chances or something > > like that. > > Thank you for testing this! > > And of course the reason that I didn't see these problems is that I > failed to update my tests to enable CONFIG_RCU_USER_QS. :-/ Also the fact that I run 32-bit guests on x86. Sigh! I take it that you are running 64-bit guests? Thanx, Paul